Automatic separation device for copying apparatus

ABSTRACT

A device comprising a ventilation plate formed therein with a multitude of openings and disposed along a path of movement of an original and a photosensitive sheet superposed one on the other with the photosensitive sheet being disposed nearer to the ventilation plate, and a cross-flow blower disposed opposite the ventilation plate with respect to the photosensitive sheet and the original. As the original and the photosensitive sheet superposed one on the other move along the path of their movement, a flow of fluid is set up by the blower and moves out of the interior of the blower through the openings in an upper half portion of the ventilation plate disposed in an outlet region of the blower. The outgoing flow of fluid is caused to change its direction of movement and move downwardly along the path of movement of the original and the photosensitive sheet whereby the original and the photosensitive sheet can be automatically separated from each other.

United States Patent Kaneda AUTOMATIC SEPARATION DEVICE FOR COPYING APPARATUS [75] Inventor: Tokuzo Kaneda, Tokyo, Japan [731 Assignee: Ricoh Co., Ltd., Tokyo, Japan [22] Filed: Oct. 29, 1973 [21] Appl. No.: 410,530

Primary ExaminerEvon C. Blunk Assistant ExaminerBruce l-i. Stoner, Jr.

Attorney, Agent, or Firm--Cooper, Dunham, Clark, Griffin & Moran [4 1 July 22, 1975 [57] ABSTRACT A device comprising a ventilation plate formed therein with a multitude of openings and disposed along a path of movement of an original and a photosensitive sheet superposed one on the other with the photosensitive sheet being disposed nearer to the ventilation plate, and a cross-flow blower disposed opposite the ventilation plate with respect to the photosensitive sheet and the original. As the original and the photosensitive sheet superposed one on the other move along the path of their movement, a flow of fluid is set up by the blower and moves out of the interior of the blower through the openings in an upper half portion of the ventilation plate disposed in an outlet region of the blower. The outgoing flow of fluid is caused to change its direction of movement and move downwardly along the path of movement of the original and the photosensitive sheet whereby the original and the photosensitive'sheet can be automatically separated from each other.

1 Claim, 2 Drawing Figures AUTOMATIC SEPARATION DEVICE FOR COPYING APPARATUS BACKGROUND OF THE INVENTION This invention relates to a device for automatically separating an original from a photosensitive sheet after the photosensitive sheet has been exposed to an optical image of the original in superposed relation in an exposing device of a copying apparatus.

In copying apparatus of the type in which an original and a photosensitive sheet are superposed one on the other to expose the photosensitive sheet to an optical image of the original or diazo type copying apparatus, for example, it is the photosensitive sheet only that is supplied to the developing section after the original and the photosensitive sheet are separated from each other. It is thus necessary to automatically separate the original and the photosensitive sheet from each other after exposure.

It has hitherto been customary to separate original from photosensitive sheet either by using a rotary guide or using air. Separation devices relying on the rotary guide are generally constructed such that, when the two sheets (the original and photosensitive sheet) are detected while being conveyed, a guide roller is rotated and the original is separated from the photosensitive sheet by a displacing roller which rotates in a direction opposite to the direction of rotation of the guide roller. In devices of this type, it is essential that the material of the rollers should be selected such that the coefficient of friction between the rollers and the sheets brought into contact with each other is higher than the coefficient of friction between the two sheets. Separation devices of this type have a disadvantage in that, since the relative velocities of the rollers in the displacing section are high, great wear is caused on the rollers and the separation capabilities of the devices are lowered with extended use. Also, when the leading end portions of the two sheets are not indexed properly with each other or the distance between the displacing roller and guide roller is not optimum, a misoperation of the devices may occur and the original may be damaged by being inadvertently delivered to the developing device. Particularly when the original only is delivered to the developing device by misoperation, difficulty is experienced in positively withdrawing the original from the developing device due to the lack of adequate means for attaining the end.

Devices of the type which relies on air are generally constructed such that two suction boxes are disposed along the path of movement of the original and photosensitive sheet superposed one on the other, one suction box disposed on one side of the path and the other suction box on the other side thereof, so that the original and photosensitve sheet are drawn by suction applied from respective suction boxes and moved away from each other while the two sheets move along the path. The devices of this type are free from the disadvantage of wear being caused thereon with extended use, but have the disadvantages of requiring a large space in which the suction boxes and a conveyor belt consisting of a number of belt members are disposed. Besides, it is necessary to use a powerful motor for operating fans for drawing the original and photosensitive sheets by suction. Ducts must be mounted in the suction boxes for venting air to atmosphere. As aforementioned, the pair of suction boxes used for the separation devices of this type are considerably large in size. Thus, they lend themselves to use with copying apparatus of the large type, but they are too expensive or occupy too much space to be used economically with medium or small copying apparatus.

SUMMARY OF THE INVENTION This invention has as its object the provision of an automatic separation device for copying apparatus for separating an original from a photosensitve sheet, obviating the aforementioned disadvantages of the prior art, which employs a cross-flow blower setting up a flow of fluid moving out of the interior of the blower through an outlet region thereof to produce a back pressure applied to the back of the original whereby the photosensitive sheet can be positively separated from the original.

The device according to the invention is capable of positively separating the photosensitive sheet from the original by using a cross-flow blower which sets up a flow of fluid moving out of the interior thereof through an outlet region so that the outgoing fluid flow produces a back pressure applied to the backside of the original whereby the original and the photosensitive sheet can be positively separated from each other. Thus the invention provides a separation device which is free from the danger of misoperation and lowered separation capabilities due to wear of the parts.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic sectional view of the automatic device for separating a copy sheet from an original comprising one embodiment of the invention; and

FIG. 2 is a perspective view of one example of the rotor means of the cross-flow blower used with the automatic separation device according to the invention.

DESCRIPTION OF A PREFERRED EMBODIMENT In FIG. 1, a transparent cylinder 1 having mounted therein a lamp for effecting exposure (not shown) rotates in the direction of an arrow, and a blade 3 secured at its base to an immovable member 2 has a free end which is maintained in contact with an outer peripheral surface of the cylinder 1. Maintained in pressing contact with the outer peripheral surface of the cylinder 1 is an endless belt 4 moves in the direction of an arrow 7 while being guided by guide rollers 5 and 6. An original 8 and a photosensitive sheet 9 superposed one on the other and released from between the endless belt 4 and cylinder 1 are guided by the blade 3 and a guide plate 11 and delivered between the roller 5 and a roller 12 which rotates in the direction of an arrow. A plurality of endless belts 14 trained over the roller 12 and another roller 13 move counter clockwise for conveying out of the apparatus the original 8 which is separated from the photosensitive sheet 9 as subsequently to be described. The original 8 separated from the photosensitive sheet 9 is delivered to an original tray 17 by a pair of delivery rollers 15 and 16 rotating in opposite directions. The transparent cylinder 1 and endless belt 4 constitute an exposing device which is known.

A bladed rotor means 21 of a cross-flow blower is mounted on a shaft 22 rotatably supported at opposite ends by side plates 23 and 24 and connected at one end to a shaft of a motor 26 through a joint 25 as shown in FIG. 2. As shown in FIG. 1, the bladed rotor means 21 is covered with a cover 27 disposed along a portion of its outer peripheral surface and the side plates 23 and 24 disposed on opposite sides of the bladed rotor means 21 as aforementioned. The rest of the outer peripheral surface of the rotor means 21 is covered with a suction plate 29 disposed on the left side thereof as shown in FIG. 1. The suction plate 29 which is bent at the middle is formed at its lowered half portion with a multitude of small openings 29b through which a flow of fluid is introduced into the blower and at its upper half portion with a multitude of small openings 29a through which the flow of air is discharged from the blower. A wind shield 31 is mounted at a lower end portion of the lower half portion of the suction plate 29 to cover the same.

The rotor means 21 is disposed in a casing 32 defined by the cover 27, side plates 23, 24 and the suction plate 29, and a fluid flow varying plate 33 is mounted in front of the bladed rotor means 21 for varying the direction of the flow of fluid set up by the blower. Guide plates 34 and 35 are intended for guiding the photosensitive sheet 9 and causing it to move to a developing station (not shown) after being separated from the original 8. A pair of delivery rollers 36 and 37 are provided for delivering the exposed photosensitive sheet 9 to the developing station.

In operation, when the motor 26 is actuated to rotate the bladed rotor means 21 in the direction of an arrow 38 in FIG. 2, a flow of fluid 41 is set up by the blower and moves out of the blower through the openings 290 formed in the upper half portion of the ventilation plate 29 disposed in an outlet region of the blower. After impinging on the guide plate 34, the flow of fluid 41 changes its direction of movement and moves downwardly as shown in FIG. 1. A part of the flow of fluid 41 moving downwardly is drawn by suction into the casing 32 through the openings 29b formed in the lower half portion of the ventilation plate 29 disposed in an inlet portion of the blower while the rest of the flow of fluid moves, as indicated at 43 in FIG. 1, toward opposite sides of a passageway defined by the ventilation plate 29 and belt 14.

After being subjected to an exposing operation, the original 8 and photosensitive sheet 9 superposed one on the other are nipped by the rollers and 12, are guided by the guide plate 42 and impinge on the ventilation plate 29. At this time, a back pressure is produced on the back side of a leading end portion 8a of the original 8 by the flow of fluid 43, with a result that the leading end portion 8a of the original 8 is released from engagement with the photosensitive sheet 9 as shown in FIG. 1. Thus the original 8 and photosensitive sheet 9 move upwardly while the former is biased toward the belt 14 and the latter is biased toward the ventilation plate 29 by a flow of fluid 44 flowing between the leading end portions of original 8 and photosensitive sheet separated from each other as aforementioned.

After being separated completely from the photosensitive sheet 9, the original 8 is nipped by the delivery rollers 15 and 16 and delivered to the original tray 17 as aforementioned. The photosensitive sheet 9 is not attracted to the ventilation plate 29 when it passes by a portion of the lower half portion of the ventilation plate 29 where the wind shield 31 is disposed, but it is attracted to the ventilation plate 29 when it passes by other portion of the lower half portion of the ventilation plate 29. Thus the photosensitive sheet 9 separated from the original 8 moves upwardly while being drawn to the ventilation plate 29 by the flow of fluid introduced through the openings 29b in the ventilation plate 29 into the blower. When the leading end portion of the photosensitive sheet 9 reaches the upper half portion of the ventilation plate 29 disposed in the outlet region of the blower, the photosensitive sheet 9 is urged to move into contact with the guide plate 34 by the flow of air discharged from the blower. Then the photosensitive sheet 8 is delivered to a developing station (not shown) by the feed rollers 36 and 37.

What I claim is:

1. An automatic separation device for copying apparatus comprising a ventilation plate consisting of an upper half portion and a lower half portion and formed therein with a multitude of openings, said ventilation plate disposed along a path of movement of an original and a photosensitive sheet released in superposed relationship from an exposing station with the photosensitive sheet being disposed nearer to the ventilation plate, a cross-flow blower adapted to set up a flow of fluid moving out of the interior of the blower through an outlet region thereof in which said upper half portion of said ventilation plate is disposed into said path through said openings in said upper half portion of said ventilation plate, and means for causing said outgoing flow of fluid to change its direction of movement after passing through said openings in said upper half portion of said ventilation plate and move downwardly along said path toward the inlet of the path, a part of said downwardly moving flow of fluid introduced through said openings in said lower half portion of said ventila' tion plate disposed in an inlet region of the blower into the interior thereof and the rest of said downwardly moving flow of fluid moving toward opposite sides of said path. 

1. An automatic separation device for copying apparatus comprising a ventilation plate consisting of an upper half portion and a lower half portion and formed therein with a multitude of openings, said ventilation plate disposed along a path of movement of an original and a photosensitive sheet released in superposed relationship from an exposing station with the photosensitive sheet being disposed nearer to the ventilation plate, a cross-flow blower adapted to set up a flow of fluid moving out of the interior of the blower through an outlet region thereof in which said upper half portion of said ventilation plate is disposed into said path through said openings in said upper half portion of said ventilation plate, and means for causing said outgoing flow of fluid to change its direction of movement after passing through said openings in said upper half portion of said ventilation plate and move downwardly along said path toward the inlet of the path, a part of said downwardly moving flow of fluid introduced through said openings in said lower half portion of said ventilation plate disposed in an inlet region of the blower into the interior thereof and the rest of said downwardly moving flow of fluid moving toward opposite sides of said path. 